The Third Generation Partnership Project (3GPP) introduced a narrowband Internet-of-Things (NB-IoT) design into its Release 13 specifications of the Long-Term Evolution (LTE) wireless mobile communications standard. For NB-IoT, due to bandwidth limitations of 180 kHz, legacy LTE techniques for hybrid automatic repeat request (HARQ) feedback may not be suitable. Accordingly, new techniques for implementing HARQ feedback for NB-IoT may be needed.